Apparatus for preforming flaps of a carton



Dec. 6, 1966 L. VADAS ETAL 3,289,553

APPARATUS FOR PERFORMING FLAPS OF A CARTON Filed Dec. 16, 1963 4 Sheets-Sheet 1 EBB INVENTORS LESLIE VADAS FREDERICK W. KENDRIOK ATTORNEY Dec. 6, 1966 L. VADAS ETAL 3,239,553

APPARATUS FOR PERFORMING FLAPS OF A CARTON Filed Dec. 16, 1963 4 Sheets-Sheet 2 VENTORS LESLIE VADAS FREDERICK w. KENDRIGK ATTORNEY Dec. 6, 1966 L. VADAS ETAL 3, 8

APPARATUS FOR PERFORMING FLAPS OF A CARTON Filed Dec. 16, 1963 4 Sheets-Sheet 5 INVENTORS LESLIE VADAS FREDERICK W. KENDRICK ATTORNEY United States Patent fiice 3,283,553 Fatented Dec. 6, 1966 3,289,553 APPARATUS FOR PREIFGRMING FLAPS OF A CARTUN Leslie Vadas, Los Gatos, and Frederick W. Kendrick, San

Jose, Calif., assignors to FMC Corporation, San lose,

Califi, a corporation of Delaware Filed Dec. 16, 1963, Ser. No. 331,007 7 Claims. ((11. 93-44) The present invention pertains to packaging equipment, and more particularly relates to apparatus for pre forming or bending end closure flaps into positions which aid in the subsequent sealing operations.

When packaging products such as milk in cartons which are made of material that is relatively thick and is difficult to bend, it is desirable to preform or bend the flaps and tabs which form the top closure prior to filling and sealing the top closure. This preforming operation reduces the amount of handling of the carton after the filling operation and also reduces the degree of force that must be applied to the carton during the sealing operation thereby minimizing the tendency of liquid in the carton to be spilled.

Because of the high resistance to bending of the flaps relative to the carton walls along preformed score line-s, it is necessary to provide an internal back-up member which engages the carton slightly below those score lines which separate the flaps from their associated walls at points adjacent the transverse mid-point of these lines in order to prevent deflection at these points and provide a sharp bend along the score lines. The end portions of each score line are adequately supported by the carton walls and accordingly do not require internal support members.

Accordingly, it is one object of the present invention to provide an apparatus for preforming end closure flaps of a carton.

Another object is to provide a carton forming apparatus having an internal back-up member for supporting portions of all walls of the carton adajcent the flap score lines.

Another object is to provide an improved carton forming apparatus of simple and reliable construction.

These and other objects and advantages of the present invention will become apparent from the following description and the accompanying drawings, in which:

FIGURE 1 is an end elevation of a portion of a carton forming and filling machine showing the carton forming apparatus of the present invention associated therewith.

FIGURE 2 is a plan of that portion of the machine shown in FIG. 1.

FIGURE 3 is a vertical section taken along lines 3-3 of FIGURE 1, certain parts being cut away.

FIGURE 4 is an enlarged perspective of a portion of the carton forming apparatus of the present invention shown in the carton receiving position, certain parts being cut away and other parts being shown in section.

FIGURE 5 is an enlarged perspective showing an open end of the carton prior to being formed by the apparatus of the present invention.

FIGURE 6 is a perspective of the end of the carton after being preformed.

FIGURE 7 is an operational view showing the carton forming apparatus in vertical central section taken transversely of the direction of travel of the carton and with the apparatus in the carton forming position.

FIGURE 8 is an operational view showing the carton forming apparatus in vertical central section taken longitudinal of the direction of travel of the cart-on and with the apparatus disposed in the carton forming position.

FIGURE 9 is an operational view taken transverse to the direction of carton travel and showing the apparatus in the position it assumes after being withdrawn from the preformed carton.

FIGURE 10 is an operational view taken longitudinally of the direction of carton travel and showing the apparatus in the position it assumes after being withdrawn from the preformed carton.

The carton forming apparatus 15 of the present invention is intended for use in a carton forming and filling machine 16 of the type disclosed in the pending application for United States Letters Patent of Hetfelfinger et al., Serial No. 216,248, which application is assigned to the assignee of the present invention, and issued on May 3, 1966 as Patent No. 3,248,841. Although the apparatus 15 is designed to replace the top forming apparatus disclosed in the Heifelfinger et al. application, it is to be understood that the apparatus 15 may be used with other types of equipment. Since the carton forming and filling machine is fully disclosed in the Heffelfinger et al. application, the parts of this machine which are associated with the apparatus 15 will only briefly be described. If a more complete description of these parts is desired, reference may be had to the Heffelfinger et a1. application.

In general, the machine 16 (FIGS. 1, 2 and 3) is arranged to process two lines of cartons and includes a pair of side-by-side intermittently driven conveyors 17 each having a plurality of upstanding, U-shaped carton engaging lugs 18 spaced at intervals therealong. A vertically elongated rectangular carton C, with its lower end sealed and with its upper end open, is fed through an associated chute 19 in upright position onto the associated conveyor 1'7 between each adjacent pair of lugs 18. Each carton, in turn, is then moved by the associated conveyor 17 to a carton forming station A (FIG. 2) at which the associated carton forming apparatus 15 of the present invention preforms the several flaps and tabs, which define the top closure, from their positions shown in FIG. 5 to the positions shown in FIG. 6.

As shown in FIGURES 5 and 6, the flaps and tabs which are subsequently sealed together to form the top closure 21 include a front flap 22 which projects upwardly from, and is a continuation of, the front carton wall 23, being connected thereto by a flap score line 24; a rear flap 26 which is slightly taller than the front flap 22 and is a continuation of a rear wall 27 to which it is connected by a flap score line 28; a left side flap 29 which is a continuation of a left side wall 31 and is connected thereto by a flap score line 32; and a right side flap 33 which is a continuation of a right side wall 34 and is connected thereto by a flap score line 35. The left side flap 29 includes a tab 36, a score line 37 which is parallel to the score line 32 and facilitates the outward bending of the tab 36, and inclined score lines 38 and 39 which divide the flap 29 into a pair of substantially triangular sections 41 and 42, and a trapezoidal section 43. Similarly, the right side flap 33 includes a tab 46, a score line 4'7 which is parallel to the score line 35 and facilitates the outward bending of the tab 46, and inclined score lines 48 and 49 which divide the left flap 33 into a pair of substantially triangular sections 51 and 52, and a trapezoidal section 53.

As mentioned above, and as indicated in FIGURE 1, the machine 16 is a two line machine, with the components associated with line L1 being identical in construction and in operation to those associated with line L2. Accordingly, whenever convenient, the description to follow will be directed only to the apparatus associated with one line and the operations performed upon one carton in that line. It will be noted, however, that the carton forming apparatus has two identical formin-g heads 61, each head being associated with one of the lines I11 or L2.

The carton forming apparatus 15 (FIGS. 1, 2 and 3) is mounted for vertical reciprocable movement on a bridge plate 63 which extends transversely across both conveyors 17 and is bolted to the upper ends of pedestals 64 and 66 that are, in turn, bolted to the frame 67 of the machine 16. A hydraulic power unit 68 has its cylinder 69 secured to the bridge plate 63 and its piston rod 71 projects downwardly through hole in the bridge plate. A forming-head support plate 72 is bolted to the piston rod 71 for vertical reciprocable movement therewith.

In order to stabilize the vertical movement of the ends of the support plate 72, racks 73 (FIGS. 2 and 3) are secured to brackets 74 which are bolted to the ends of the plate 72 and project upwardly through holes 75 in the bridge plate 63. Pinions 76, which are keyed to opposite ends of a stabilizing shaft 78 are received in meshing engagement with the associated racks 73. The stabilizing shaft 78 is journal-led in bearings 79 bolted to the bridge plate 63. Thus, it will be seen that any force tending to resist movement of one end of the support plate 72 will be transmitted to the other end of the plate 72 by the stabilizing shaft 78 and the associated racks and pinions thereby assuring that both ends of the support plate 72 will be maintained at equal elevations.

Guide blocks 81 having keyways 82 (FIG. 1) therein are bolted to the bridge plate 63 adjacent associated ones of the brackets 74. Keys 83 secured to the bracket 74 are slidably received in the keyways 82 and aid in accurately guiding the forming head support plate 72 along a vertical path during its reciprocable movement.

As mentioned the above-described stabilizing shaft 78 assures that the ends of the support plate 72 will be at the same elevation during vertical movement. The guide blocks 81 assure that the movement of the plate 72 will be along a path normal to the carton supporting surface of the conveyor 17, the U-shaped lugs 18 accurately position the cartons at the carton forming station A longitudinally of the conveyor 17, and, a plurality of nylon guide rails 86 assure that the cartons will be accurately positioned transversely of the conveyor 17 while in the forming station A. The nylon guide rails 86 are secured to U-shaped brackets 87 (FIG. 1), the outer brackets being bolted to the pedestals 64 or 66 while the inner brackets 87 are secured to an upright post 88 that is bolted to the frame 67 of the machine. With the vertical movement of the support plate 72 accurately controlled as above-described, and with the cartons accurately positioned at the forming station A, it has been found that the forming head 61 will register correctly with each and every carton, in turn, and will properly form the top closure of the same.

The forming head 61 (FIG. 4) comprises an external flap bending die 91 which is fixed to the support plate 72, and an internal flap support 92 which is movable relative to the flap bending die 91. The internal flap support 92 is first moved downwardly into the open upper end of the carton and, thereafter, the external flap bending die 91 is moved downwardly to engage and bend the flaps against the resistance of the internal support 92 to thereby preform or bend the flaps into the desired position.

The internal flap support 92 comprises a frusto-conical back-up member 93 having a circular peripheral edge 94 which, when in operative position, is positioned slightly below and closely adjacent to the horizontal score lines 24, 32, 28 and 35 which connect the several flaps to the associated walls of the carton. A chamfered or frustoconical flap guiding surface 96 serves to guide the backup member 93 into the open upper end of the cartons.

The back-up member 93 is rigidly secured to an up war-dly projecting rod 97 that is slidably received in a suitably bushed guide block 98, welded to the support plate 72, and in an opening (not shown) in the bridge plate 63. Lock nuts 99 (FIG. 1) are screwed onto the upper end of the rod 97 and are adjusted and locked in position so as to hold the peripheral edge 94 of the backup member 93 slightly below the horizontal plane of the flap score lines when the back-up member 93 is in its lowermost position. A collar 101 is rigidly secured to the rod 97 intermediate the bridge plate 63 and the guide block 98, so that after a predetermined amount of upward movement of the support plate 72 takes place, the collar 101 engages the upper end of the guide block 98 and causes the internal flap support 92 to move upwardly therewith. Rubber washers 103 are disposed between the collar 101 and the block 98, and between the lock nuts 99 and the bridge plate 63, to reduce shock and minimize noise.

The external flap bending die 91 comprises a front flap breaking shoe 106 (FIG. 8) of generally triangular cross-section, a rear generally triangular flap breaking shoe 107, a pair of corner shoes 108 and 109 arranged to engage the left flap 29, a pair of corner shoes 111 and 112 arranged to engage the right flap 33, and opposed fingers 113 and 114 arranged to engage the tabs 36 and 46, respectively, to bend the tabs outwardly. The corner shoes 108 and 109 are welded to a bar 116, and the shoes 111 and 112 are similarly welded to a bar 117. The fingers 113 and 114 are slotted and are bolted to the bars 116 and 117, respectively, so that minor vertical adjustment can be made. Similarly, the shoes 106 and 107, and the bars 116 and 117 are bolted to a slotted head plate 118 so as to permit the slight horizontal adjustment of the shoes and bars relative to the head plate. The head plate 118 is rigidly secured to the support plate 72 as by bolting.

After the frusto-conical back-up member 93 has moved downwardly within the open end of the carton to its lowermost position, continued downward movement of the external bending die 91 causes carton-engaging surfaces 121 (FIGS. 7 and 9) of the four corner shoes 108, 109, 111 and 112 to engage and bend inwardly the trapezoidal sections 43 and 53 of the left and right side flaps 29 and 33, respectively. Shortly after initial engagement by the corner shoes, bevelled edges 122 (FIGS. 8 and 10) and inclined flap bending surfaces 124 of the front and rear shoes 106 and 107 engage the front and rear flaps 22 and 26, respectively, and bend them inwardly. At the lowermost extent of travel of the external flap bending die 91, points on the outer peripheral edge 94 of the back-up member 93 are spaced from the shoes 106 and 107 a distance slightly greater than the thickness of the carton walls thereby causing sharp bends to occur at the score lines 24 and 28.

The front flap breaking shoe 106 is also provided with chamfered vertical edges 106a (FIG. 4) which aid in guiding the shoe 106 between the forward upper edges of the side flaps 29 and 33. Also during downward movement of the external front bending die 91, the fingers 113 and 114 (FIG. 7) engage and bend the tabs 36 and 46 outwardly.

It is to be particularly noted that the internal back-up member 93 has a circular, rather than a rectangular or square periphery. With this arrangement no difficulty is encountered in inserting the member 93 within the carton in the event the upper end of the carton i not held in the intended square shape due to internal forces acting on the carton walls which tend to collapse the upper end of the carton. Even if the carton is deflected out of its normal position, the flap guiding surface 96 will engage and guide the back-up member 93 into the carton.

The use of a back-up member 93 having a circular periphery has the advantage of providing a rigid support intermediate the ends of each score line, and yet permits the internal member 93 to be withdrawn from the carton after the flaps have been formed without applying an excessive lifting force to the carton. However, in order to positively prevent the carton from being lifted during withdrawal of the back-up member from the formed carton, the lower nylon guide rails 86 (FIG. 1) are spaced apart a distance slightly less than the width of the carton thereby pinching the carton and preventing upward movement of the same.

Since the control mechanism for operating the power units 68 in timed relation with the movement of the conveyor 17 is not a feature of the present invention, the control mechanism will not be described herein. Reference may be had to the aforementioned Heifelfinger et al. application if a description of the control mechanism is desired.

In the operation of the carton forming apparatus 15 of the present invention, the conveyor 17 (FIGS. 1 and 3) indexes a carton into the carton forming station A with the carton flaps being positioned as shown in FIG- URE 5.

The nylon guide rails 86 center the carton transversely of the conveyor and the lower rails additionally pinch the carton to prevent it from being lifted during subsequent withdrawal of the back-up member 93 from within the carton. The U-shaped lugs 18 center the carton longitudinally under the forming head 61.

With the carton indexed at the forming station A and centered as above described, the power unit 68 is activated to lower the forming head 61. The back-up member 93 then enters the carton and move downwardly within the carton until the circular edge 94 becomes disposed slightly below the horizontal plane of the flap score lines and the nuts 99 engage the washer 103 and terminates further movement. The beveled flap guiding surface 96 assures that the member 99 will be properly guided into the carton. The external flap bending die 91 then continues downwardly causing the carton engaging surfaces 121 (FIGS. 7 and 9) of the corner shoes 108, 109, 111 and 112 to engage and fold the trapezoidal sections 43 and 53 of the side flaps inwardly. After side flaps 29 and 33 have started to bend inwardly, the end fiaps are engaged by the inclined flap bending surface 124 (FIGS. 8 and 10) of the front and rear flap breaking shoes 106 and 107. Also at this time, the tab breaking fingers 113 and 114 contact and bend the tabs 36 and 46 outwardly as illustrated in FIGURE 7.

With the top closure 21 of the carton so formed, the power unit 68 then moves the support plate '72 upwardly thereby initially moving the external flap bending die 91 upwardly and away from the carton flaps and from the back-up member 93. The collar 191 is then engaged by the washer 103 and is moved upwardly causing the back-up member 3 to be pulled out of the formed top closure of the carton. Because the periphery of the back-up member is circular, rather than square, ample space exists adjacent the corners of the carton to permit the back-up member 93 to be withdrawn without undue resistance against the inwardly bent surfaces of the top closure.

It will be apparent from the foregoing description that the carton forming apparatus of the present invention utilizes .a circular back-up member which may be easily guided into a carton, and which may be withdrawn from the carton after the flaps of the top closure have been bent inwardly without danger of becoming bound within the carton. The carton forming apparatus is also of simple design and is easily operated and maintained.

While one embodiment of the present invention has been shown and described, it will be understood that various changes and modifications may be made without departing from the spirit of the invention or the scope of the appended claims.

The invention having thus been described, what is believed to be new and desired to be protected by Letters Patent is:

1. An apparatus for preforming end closure flaps of a carton comprising back-up means having a circular periphery, means for moving said back-up means into said carton and for holding said back-up means in fixed position within said carton, certain portions of the circular periphery of said back-up means defining folding surfaces disposed immediately adjacent the transverse mid-point of each wall, and external flap bending means connected to said moving means for movement against the external surfaces of the flap for bending the flaps inwardly about said folding surfaces of said backup means, said circular periphery of said back-up means permitting the back-up means to be reliably guided into the carton and to be easily withdrawn from the carton after the end closure flaps are preformed.

2. An apparatus for preforming end closure flaps of a carton comprising back-up means having a circular periphery defined by a frus-to-conical flap guiding surface and a frusto-conical back-up surface, means for moving said back-up means into said carton and for holding said back-up means in fixed position within said carton, certain portions of said circular periphery of said back-up means defining folding surfaces disposed immediately adjacent the transverse mid-point of each wall, and external flap bending means connected to said moving means for movement against the external surfaces of the flaps for bending the flaps inwardly about said folding surfaces of said back-up means, said circular periphery of said back-up means permitting the back-up means to be reliably guided into the carton and to be easily withdrawn from the carton after the end closure flaps are preformed.

3. An apparatus for preforming end closure flaps of a carton comprising back-up means having a circular periphery defined by a frusto-conical flap guiding surface and a frusto-conical back-up surface, means for moving said back-up means into said carton and for holding said back-up means in fixed position within said carton, certain portions of said circular periphery of said back-up means defining folding surfaces disposed immediately adjacent the transverse mid-point of each wall, and external flap bending means including a plurality of flap breaking shoes for engaging said flaps and for bending said flaps inwardly, all of said flap breaking shoes being rigidly attached to each other and each shoe having a surface which is moved to a position closely .adjacent a point on said circular periphery to provide a sharp bend of the carton walls at each of said points, said circular periphery of said back-up means permitting the back-up means to be reliably guided into the cart-on and to be easily withdrawn from the carton after the end closure flaps are preformed.

4. An apparatus for preforming end closure flaps and tabs of a carton comprising back-up means having a circular periphery defined by a frusto-conical flap guiding surface and the frusto-conical back-up surface; means for moving said back-up means into said carton and for holding said back-up means in fixed position within said carton, certain portions of said circular periphery of said back-up means defining folding surfaces disposed immediately adjacent the transverse mid-point of each wall; and external flap bending means including a plurality of flap breaking shoes for engaging said flaps and for bending said flaps inwardly, and a. pair of tab breaking fingers for engaging said tabs and bending the same outwardy, all of said flap breaking shoes and tab breaking fingers being rigidly attached to each other and each flap breaking shoe having a surface which is moved to a position closely adjacent a point on said circular periphery to provide a sharp bend of the carton walls at each of said points, said tab breaking fingers bending the tabs outwardly and closely adjacent said frusto-conical back-up surface when said flap breaking shoes are closely adjacent said points on the circular periphery, said circular periphery of said back-up means permitting the back-up means to be reliably guided into the carton and to be easily withdrawn from the carton after the end closure flaps are preformed.

5. An apparatus for preforming end closure flaps of a rectagular carton comprising back-up means having a periphery defining arcuate folding surfaces and movable into said carton to a predetermined back-up position, said back-up means having said arcuate folding surfaces disposed adjacent and tangent to the transverse mid-point of each wall, external flap bending means movable relative to said back-up means for movement against the external surfaces of the flaps to move the flaps inwardly about said 'folding surfaces of said backup means, means connecting said back-up means to said flap bending means for relative movement therebetween to cause the back-up means to enter said carton prior to the engagement of said flap bending means with said carton and to cause the flap bending means to move away from the preformed end closure of the carton prior to the withdrawal of the back-up means from the carton, and means for reciprocating said connecting means.

6. An apparatus for preforming four end closure flaps of a rectangular carton having four walls comprising means for moving the carton into a forming station, means for functionally gripping the lower end of the carton to hold the carton from vertical movement While in the forming station, back-up means movable into said carton into a predetermined back-up position, said backup means having a periphery defining arcuate folding surfaces disposed tangent to and adjacent the transverse mid-point of the four walls, external fiap bending means movable relative to said back-up means for movement against the external surface of the four flaps to move the flaps inwardly about said folding surfaces of said back-up means, means connecting said back-up means to said flap bending means for relative movement therebetween to cause the backup means to enter said carton prior to the engagement of said flap bending means with said four flaps and to cause the flap bending means to be moved away from the preformed end closure of the carton prior to the withdrawal of the back-up means from the carton, and means for reciprocating said connecting means.

7. An apparatus for preforming end closure flaps of a rectangular carton comprising a pair of intermittently indexed conveyors for indexing a pair of cartons into a carton forming station, a horizontal support bridge disposed in fixed position at said forming station above said conveyors, a forming head support, collar means centrally connected to said forming head support and arranged to vertically reciprocate said forming head support when said cartons are indexed at said forming station, stabilizing means connected to the ends of the forming head support for maintaining said support in level orientation and for guiding said ends for vertical movement; a pair of forming heads carried by said forming head support, each forming head having an external fiap breaking member rigidly secured to said forming head support for movement therewith and an internal flap support member carried by said forming head support, said internal support being vertically movable relative to said external member and including a back-up member having a circular periphery and having means engageable with said bridge to limit the downward movement of the same and to position the periphery in a predetermined plane whereupon downward movement of said support causes said back-up member to enter its associated carton and terminate movement at said pre-- determined plane, and thereafter causes said external member to engage and bend the associated flaps about said circular periphery of said stabilizing means assuring that both of said external flap breaking members uniformly engage and bend the associated carton flaps inwardly, said circular periphery of said back-up means permitting the back-up means to be reliably guided into the carton and to be easily withdrawn from the carton after the end closure flaps are preformed.

References Cited by the Examiner UNITED STATES PATENTS BERNARD STICKNEY, Primary Examiner. 

1. AN APPARATUS FOR PREFORMING END CLOSURE FLAPS OF A CARTON COMPRISING BACK-UP MEANS HAVING A CIRCULAR PERIPHERY, MEANS FOR MOVING SAID BACK-UP MEANS INTO SAID CARTON AND FOR HOLDING SAID BACK-UP MEANS IN FIXED POSITION WITHIN SAID CARTON, CERTAIN PORTIONS OF THE CIRCULAR PERIPHERY OF SAID BACK-UP MEANS DEFINING FOLDING SURFACES DISPOSED IMMEDIATELY ADJACENT THE TRANSVERSE MID-POINT OF EACH WALL, AND EXTERNAL FLAP BENDING MEANS CONNECTED TO SAID MOVING MEANS FOR MOVEMENT AGAINST THE EXTERNAL SURFACES OF THE FLAP FOR BENDING THE FLAPS INWARDLY ABOUT SAID FOLDING SURFACES OF SAID BACKUP MEANS, SAID CIRCULAR PERIPHERY OF SAID BACK-UP MEANS PERMITTING THE BACK-UP MEANS TO BE RELIABLY GUIDED INTO THE CARTON AND TO BE EASILY WITHDRAWN FROM THE CARTON AFTER THE END CLOSURE FLAPS ARE PREFORMED. 